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CPT®
84510

CPT® Code 84510

Official Description

Tyrosine

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The CPT® Code 84510 refers to a laboratory test specifically designed to measure the levels of tyrosine in the blood. Tyrosine is classified as a nonessential amino acid, meaning that the body can synthesize it from another amino acid called phenylalanine. This amino acid plays a crucial role in the production of several important neurotransmitters, including dopamine, epinephrine, and norepinephrine, which are vital for various physiological functions, including mood regulation and stress response. Additionally, tyrosine is essential for the proper functioning of the adrenal, thyroid, and pituitary glands, which are key components of the endocrine system. In certain individuals, particularly those with the genetic disorder known as phenylketonuria (PKU), tyrosine levels may be significantly decreased. This condition arises because the body is unable to properly synthesize phenylalanine, leading to a deficiency in tyrosine. The measurement of tyrosine levels can therefore provide important diagnostic information regarding metabolic disorders and the overall amino acid balance in the body. To perform this test, a blood sample is collected through a procedure known as venipuncture, which is separately reportable. The plasma obtained from the blood sample is then analyzed using a technique called ion exchange chromatography, a method that allows for the precise separation and quantification of amino acids in the plasma. This comprehensive approach ensures accurate assessment of tyrosine levels, aiding in the diagnosis and management of related health conditions.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The CPT® Code 84510 is indicated for use in various clinical scenarios where the measurement of tyrosine levels is necessary. The following conditions and situations may warrant this test:

  • Phenylketonuria (PKU) - This genetic disorder leads to an inability to metabolize phenylalanine, resulting in decreased levels of tyrosine. Testing for tyrosine can help assess the metabolic status of individuals with PKU.
  • Assessment of Amino Acid Metabolism - The test may be utilized to evaluate overall amino acid metabolism, particularly in patients presenting with symptoms of metabolic disorders.
  • Monitoring of Thyroid Function - Since tyrosine is involved in the synthesis of thyroid hormones, measuring its levels can provide insights into thyroid gland function.
  • Evaluation of Neurotransmitter Synthesis - Given tyrosine's role in producing neurotransmitters, this test may be indicated in patients with neurological or psychiatric conditions where neurotransmitter levels are of concern.

2. Procedure

The procedure for obtaining a tyrosine level measurement involves several key steps, which are outlined below:

  • Step 1: Patient Preparation - Prior to the blood draw, the patient may be instructed to fast or avoid certain medications that could affect amino acid levels. It is essential to follow any specific guidelines provided by the healthcare provider to ensure accurate test results.
  • Step 2: Venipuncture - A qualified healthcare professional performs venipuncture, which involves inserting a needle into a vein, typically in the arm, to collect a blood sample. This step is crucial as it provides the necessary specimen for analysis. The site is usually cleaned with an antiseptic to minimize the risk of infection.
  • Step 3: Sample Collection - The blood is collected into a designated tube, often containing an anticoagulant to prevent clotting. The volume of blood collected must be sufficient for the subsequent analysis of tyrosine levels.
  • Step 4: Plasma Separation - After collection, the blood sample is processed to separate the plasma from the cellular components. This is typically done through centrifugation, which spins the sample at high speeds to separate the components based on density.
  • Step 5: Ion Exchange Chromatography - The separated plasma is then subjected to ion exchange chromatography, a laboratory technique that allows for the precise measurement of amino acids, including tyrosine. This method separates the amino acids based on their charge and allows for accurate quantification.

3. Post-Procedure

After the procedure, the patient may experience minimal discomfort at the venipuncture site, which typically resolves quickly. There are generally no specific post-procedure care instructions required for this test, but patients should be advised to apply pressure to the site to minimize bruising. The results of the tyrosine level test will be analyzed and reported by the laboratory, and the healthcare provider will discuss the findings with the patient, including any necessary follow-up actions based on the results.
Short Descr ASSAY OF TYROSINE
Medium Descr ASSAY OF TYROSINE
Long Descr Tyrosine
Status Code Statutory Exclusion (from MPFS, may be paid under other methodologies)
Global Days XXX - Global Concept Does Not Apply
PC/TC Indicator (26, TC) 9 - Not Applicable
Multiple Procedures (51) 9 - Concept does not apply.
Bilateral Surgery (50) 9 - Concept does not apply.
Physician Supervisions 09 - Concept does not apply.
Assistant Surgeon (80, 82) 9 - Concept does not apply.
Co-Surgeons (62) 9 - Concept does not apply.
Team Surgery (66) 9 - Concept does not apply.
Diagnostic Imaging Family 99 - Concept Does Not Apply
CLIA Waived (QW) No
APC Status Indicator Conditionally packaged laboratory tests
Type of Service (TOS) 5 - Diagnostic Laboratory
Berenson-Eggers TOS (BETOS) T1H - Lab tests - other (non-Medicare fee schedule)
MUE 1
CCS Clinical Classification 233 - Laboratory - Chemistry and Hematology
90 Reference (outside) laboratory: when laboratory procedures are performed by a party other than the treating or reporting physician or other qualified health care professional, the procedure may be identified by adding modifier 90 to the usual procedure number.
Date
Action
Notes
2013-01-01 Changed Medium Descriptor changed.
Pre-1990 Added Code added.
Code
Description
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